Snowplow blade

ABSTRACT

A snowplow blade mounted at the forward end of a vehicle is set obliquely with respect to the forward direction of travel, the snowplow blade presenting a forwardly directed concave face defining a lower scraping edge, a top edge, and respective leading and trailing lateral edges, the shape and setting of the blade being such that a line extending diagonally across the blade face from the leading end of the lower scraping edge to the trailing end of the top edge intersects the lower scraping edge at an angle which is greater than the acute angle subtended between the lower scraping edge and said forward direction of travel.

[ Oct. 2, 1973 1 SNOWPLOW BLADE [75] Inventors: David M. Henry,Kitchener, Ontario;

Jan H. Verseei, Preston, Ontario, both of Canada [731 Assignee: EasternSteel Products Ltd., Preston,

Ontario, Canada 22 Filed: Aug. 10,1971

21 Appl. No.2 170,450

[52] U.S. Cl 37/41, 37/50, 172/801 [51] E0lh 5/00 [58] Field of Search37/41, 44, 42, 50-53, 37/35; 172/770, 771, 801, 276

[56] References Cited UNITED STATES PATENTS 2,430,221 11/1947 Frink eta1. 37/42 R 2,651,121 9/1953 Shannon 37/42 R 2,778,126 1/1957 Shannon37/42 R 1,698,809 1/1929 Angell 37/42 1,867,255 7/1932 De Lamater...37/42 R 6,379 4/1849 Finney 172/770 2,849,940 9/1958 Haynes 172/7701,225,659 5/1917 Lawrence 172/771 X FOREIGN PATENTS OR APPLICATIONS97,682 12/1939 Sweden 37/50 562,934 9/1958 Canada 37/50 445,942 1/1948Canada 23,400 8/1949 Finland 106,239 1/1943 Sweden 92,193 5/1938 Sweden37/42 R Primary Examiner-Robert E. Pulfrey Assistant ExaminerEugene H.Eickholt Attorney-J. A. Legris et a1.

[57] ABSTRACT A snowplow blade mounted at the forward end of a vehicleis set obliquely with respect to the forward direction of travel, thesnowplow blade presenting a forwardly directed concave face defining alower scraping edge, a top edge, and respective leading and trailinglateral edges, the shape and setting of the blade being such that a lineextending diagonally across the blade face from the leading end of thelower scraping edge to the trailing end of the top edge intersects thelower scraping edge at an angle which is greater than the acute anglesubtended between the lower scraping edge and said forward direction oftravel.

3 Claims, 6 Drawing Figures PATENTEDBBT '2 3,762,077

lnvenTors David M. Henry Jon H.Versee way A Horn eys PATENTEDUBT 23.762.077

SHEET 2 or 2 lnvenrors David M. Henr Tan H. Versee) WMQM ,4 HorneygSNOWPLOW BLADE This invention relates generally to snowplows and toblade or moldboards therefor. The invention is concerned particularlywith snowplows designed to operate at high speeds.

When considering the operation of snowplows it is appropriate toconsider two ranges of operating speeds in which the snow flow patternsacross the blade face are quite different. In the lower of the ranges,typically up to m.p.h., the snow encountered by the blade is not liftedto the top of the blade but is simply carried sideways with a rollingaction and deposited just beyond the trailing edge of the blade. In theupper range, typically above 15 20 m.p.h., the velocity is sufficient tocast the snow laterally from the blade.

The problems of blade design are different for the two speed ranges. Inthe lower speed range the blade simply pushes the snow and its shape isrelatively unimportant. In the upper speed range the cast distance is ofmajor concern as also is the problem of minimizing the impairment ofvisiblity through snow passing over the top edge of the blade, and inpractice a compromise is usually sought.

It is one object of the present invention to provide a bladeconstruction which ensures maximum visibility at high speeds.

It is another object of the present invention to provide a bladeconstruction which ensures maximum visibility at high speeds and whichis designed to increase the distance of cast.-

Accordingly the invention provides in combination with a vehicle havinga forward direction of travel, a snowplow blade mounted at the forwardend of the vehicle and ste obliquely with respect to the forwarddirection of travel, the snowplow blade presenting a forwardly directedconcave face defining a lower scraping edge, a top edge, and respectiveleading and trailing lateral edges, the shape and setting of the bladebeing such that a line extending diagonally across the blade face fromthe leading end of the lower scraping edge to the trailing end of thetop edge intersects the lower scraping edge at an angle which is greaterthan the acute angle subtended between the lower scraping edge and saidforward direction of travel.

A feature of the invention is that the snowplow blade has an extensionprojecting laterally from said trailing lateral edge, the extensionpresenting a forwardly directed concave face contiguous with saidconcave face of the blade and subtending an obtuse angle therewithwhereby to intersect and deflect snow directed across said trailinglateral edge of the blade face.

In order that the invention may be readily understood, two embodimentsthereof will now be described by way of example with reference to theaccompanying drawings, in which:

FIG. 1 is a side elevation of a snowplow provided with a moldboard orplowblade according to the present invention;

FIG. 2 is a plan view of the snowplow shown in FIG.

FIG. 3 is a front perspective view of the plowblade;

FIG. 4 is a developed plan view of the plowblade;

FIG. 5 is a front perspective view of an alternative plow blade inaccordance with the invention; and

FIG. 6 is a developed plan view of the plowblade shown in FIG. 5.

The snowplow illustrated in FIGS. 1 and 2 comprises a truck 10 having amounting means 11 at its forward end by which a snowplow blade 12 ismounted on the truck. The blade 12 is set obliquely with respect to theforward direction of travel of the truck, at an angle 0, as indicated inFIG. 2. The blade 12 has a forwardly directed concave face 13 whichdefines a lower scraping edge 14, a top edge 15, leading and trailinglateral edges l6, l7, and an oblique edge 18 extending from the trailingend of the lower scraping edge 14 and intersecting the trailing lateraledge 17. The configuration of the blade is of critical importance, andfor clear identification these edges are also identified by the samereference numerals in FIGS. 3 6.

The snowplow blade of FIGS. 1 4 also has an extension 19 projectinglaterally from the trailing edge of the blade face 13, the extensionpresenting a forwardly directed concave face contiguous with the concaveface of the blade and subtending an obtuse angle with it which variesfrom a maximum value at each end of the trailing edge 17 to a minimumvalue at an intermediate position. The snowplow blade of FIGS. 5 and 6is generally similar to that of FIGS. 1 4, and is adapted to be mountedon the truck in the same way as the latter, but does not have thelateral extension 19 projecting from the trailing edge of the bladeface. To simplify the description, the configuration of the simplerblade of FIGS. 5 and 6 will be described first.

Referring to FIGS. 5 and 6, the blade is arranged to be mounted so thatits lower scraping edge 14 subtends an angle 0 with the forwarddirection of travel; the width of path that the blade will clear isobviously given by L Sin 9, where L is the length of the scraping edge14. The blade is' designed primarily for use at high speeds, that is tosay at speeds of 20 m.p.h. and higher, and it is therefore an importantrequirement of the design that snow lifted across the blade face shouldnot be lifted across the top edge 15 of the blade. Ideally the snowshould be wholly diverted across the lateral trail-.

ing edge 17, as indicated by the snow flow lines X,Y,Z. As seen in thedeveloped plan view of FIG. 6, this requirement is met if the extremeflow line Z, extending along the longitudinal line A-B, intersects theedge 17. Therefore the condition that snow should not be diverted overthe top. edge 15 is that a line AC extending diagonally across the bladeface from the leading end A of the lower scraping edge to the trailingend C of he top edge should intersect the scraping edge 14 at an anglewhich is greater than the acute angle 0 subtended between the lowerscraping edge and the forward direction of travel (or the line A-B).

By providing the oblique edge 18 it is ensured that all snow interceptedby the scraping edge of the blade has to travel a substantial distanceacross the blade face.

Clearly the oblique edge must not intersect any of the flow lines. Ittherefore follows that the oblique edge 18 must subtend an obtuse anglewith the lower scraping edge 14 which is greater than the complement ofthe angle 0.

The blade configuration shown in FIGS. 3 and 4 is essentially similar tothat of FIGS. 5 and 6, and corresponding parts are denoted by the samereference numerals and letters. However, snow diverted across thetrailing edge 17 of the blade face is caused to flow across the face ofthe extension 19, which is shaped so as to convSrge the snow flow lines.The extension is designed so as to increase the distance to which snowiS cast laterally from the snowplow. To this end the concave face of theextension subtends an obtuse angle with the concave face of the blade.It is found in practice that the maximum cast is achieved when thisangle varies from a maximum value at each end of the trailing edge 17,to a minimum value at an intermediate position, the minimum value beingbetween (90 and (115 6), where 6 is the acute angle subtended betweenthe lower scraping edge and the forward direction of travel.

What we claim as our invention is:

1. In combination with a vehicle having a forward direction of tavel, asnowplow blade mounted at the forward end of the vehicle and setobliquely with respect to the forward direction of travel, the snowplowblade presenting a forwardly directed concave face defining a lowerscraping edge, a top edge, and respective leading and trailing lateraledges, the shape and setting of the blade being such that a lineextending diagonally across the blade face from the leading end of thelower scraping edge to the trailing end of the top edge intersects thelower scraping edge at an angle which is greater than the acute anglesubtended between the lower scraping edge and said forward direction oftravel, the concave face of the blade further defining an oblique edgeextending from the trailing end of the lower scraping edge andintersecting said trailing lateral edge, the oblique edge subtending anobtuse angle with the lower scraping edge which is greater than thecomplement of said acute angle, the snowplow blade having an extensionprojecting laterally from said trailing lateral edge, the extensionpresenting a forwardly directed concave face continguous with saidconcave face of the blade and subtending an obtuse angle therewithwhereby to intersect and deflect snow directed across said trailinglateral edge of the blade face.

2. In combination with a vehicle having a forward direction of travel, asnowplow blade mounted at the forward end of the vehicle and setobliquely with respect to the forward direction of travel, the snowplowblade presenting a forwardly directed concave face defining a lowerscraping edge, a top edge, and respective leading and trailing lateraledges, the shape and setting of the blade being such that a lineextending diagonally across the blade face from the leading end of thelower scraping edge to the trailing end of the top edge intersects thelower scraping edge at an angle which is greater than the acute anglesubtended between the lower scraping edge and said forward direction oftravel, the snowplow blade having an extension projecting laterally fromsaid trailing lateral edge, the extension presenting a forwardlydirected concave face contiguous with said concave face of the blade andsubtending therewith an obtuse angle which varies from a maximum valueat each end of the trailing edge to a minimum value at an intermediateposition, said minimum value being between 6) and 0 where 0 is the acuteangle subtended between the lower scraping edge and the forwarddirection of travel.

3. In combination: a snowplow blade and vehicle mounting means therefor,said vehicle mounting means being connected to the blade to set theblade obliquely with respect to a forward direction of travel, thesnowplow blade presenting a forwardly directed concave face defining alower scarping edge, a top edge, and respective leading and trailinglateral edges, the shape and setting of the blade being such that theline extending diagonally across the blade face from the leading end ofthe lower scraping edge to the trailing edge of the top edge intersectsthe lower scraping edge at an angle which is greater than the acuteangle subtended between the lower scraping edge and said forwarddirection of travel, the snowplow blade having an extension projectinglaterally from said trailing lateral edge, the extension presenting aforwardly directed concave face contiguous with said concave face of theblade and subtending therewith an obtuse angle which varies from amaximum value at each end of the trailing edge to a minimum value at anintermediate position, said minimum value being between (90 0) and (l 150 where 0 is the acute angle subtended between the lower scraping edgeand the forward direction of travel. =8

1. In combination with a vehicle having a forward direction of tavel, a snowplow blade mounted at the forward end of the vehicle and set obliquely with respect to the forward direction of travel, the snowplow blade presenting a forwardly directed concave face defining a lower scraping edge, a top edge, and respective leading and trailing lateral edges, the shape and setting of the blade being such that a line extending diagonally across the blade face from the leading end of the lower scraping edge to the trailing end of the top edge intersects the lower scraping edge at an angle which is greater than the acute angle subtended between the lower scraping edge and said forward direction of travel, the concave face of the blade further defining an oblique edge extending from the trailing end of the lower scraping edge and intersecting said trailing lateral edge, the oblique edge subtending an obtuse angle with the lower scraping edge which is greater than the complement of said acute angle, the snowplow blade having an extension projecting laterally from said trailing lateral edge, the extension presenting a forwardly directed concave face continguous with said concave face of the blade and subtending an obtuse angle therewith whereby to intersect and deflect snow directed across said trailing lateral edge of the blade face.
 2. In combination with a vehicle having a forward direction of travel, a snowplow blade mounted at the forward end of the vehicle and set obliquely with respect to the forward direction of travel, the snowplow blade presenting a forwardly directed concave face defining a lower scraping edge, a top edge, and respective leading and trailing lateral edges, the shape and setting of the blade being such that a line extending diagonally across the blade face from the leading end of the lower scraping edge to the trailing end of the top edge intersects the lower scraping edge at an angle which is greater than the acute angle subtended between the lower scraping edge and said forward direction of travel, the snowplow blade having an extension projecting laterally from said trailing lateral edge, the extension presenting a forwardly directed concave face contiguous with said concave face of the blade and subtending therewith an obtuse angle which varies from a maximum value at each end of the trailing edge to a minimum value at an intermediate position, said minimum value being between (90* + theta ) and (115* + theta ) where theta is the acute angle subtended between the lower scraping edge and the forward direction of travel.
 3. In combination: a snowplow blade and vehicle mounting means therefor, said vehicle mounting means being connected to the blade to set the blade obliquely with respect to a forward direction of travel, the snowplow blade presenting a forwardly directed concave face defining a lower scarping edge, a top edge, and respective leading and trailing lateral edges, the shape and setting of the blade being such that the line Extending diagonally across the blade face from the leading end of the lower scraping edge to the trailing edge of the top edge intersects the lower scraping edge at an angle which is greater than the acute angle subtended between the lower scraping edge and said forward direction of travel, the snowplow blade having an extension projecting laterally from said trailing lateral edge, the extension presenting a forwardly directed concave face contiguous with said concave face of the blade and subtending therewith an obtuse angle which varies from a maximum value at each end of the trailing edge to a minimum value at an intermediate position, said minimum value being between (90* + theta ) and (115* + theta ) where theta is the acute angle subtended between the lower scraping edge and the forward direction of travel. 